From c353e2597f7f24afbcd3bb34753d3e580bcee8ad Mon Sep 17 00:00:00 2001 From: Benjamin Barenblat Date: Thu, 8 Dec 2022 10:59:50 -0800 Subject: Eliminate AArch64-specific code paths from LowLevelHash MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit After internal investigation, it’s no longer clear that the alternative LowLevelHash mixer committed in a05366d851c5cb88065272f951e03955197e7c11 unequivocally improves performance on AArch64. It unnecessarily reduces performance on Apple Silicon and the AWS Graviton. It also lowers hash quality, which offsets much of the performance gain it provides on the Arm Neoverse N1 (see https://github.com/abseil/abseil-cpp/issues/1093). Switch back to the original mixer. Closes: https://github.com/abseil/abseil-cpp/issues/1093 PiperOrigin-RevId: 493941913 Change-Id: I84c789b2f88c91dec22f6f0f6e8c5129d2939a6f --- absl/hash/internal/low_level_hash_test.cc | 48 ------------------------------- 1 file changed, 48 deletions(-) (limited to 'absl/hash/internal/low_level_hash_test.cc') diff --git a/absl/hash/internal/low_level_hash_test.cc b/absl/hash/internal/low_level_hash_test.cc index ae930b34..589a3d8f 100644 --- a/absl/hash/internal/low_level_hash_test.cc +++ b/absl/hash/internal/low_level_hash_test.cc @@ -452,54 +452,6 @@ TEST(LowLevelHashTest, VerifyGolden) { 0xdd497891465a2cc1, 0x6f1fe8c57a33072e, 0x2c9f4ec078c460c0, 0x9a725bde8f6a1437, 0x6ce545fa3ef61e4d, }; -#elif defined(__aarch64__) - constexpr uint64_t kGolden[kNumGoldenOutputs] = { - 0x45c0aadee165dcbe, 0x25ed8587f6f20d06, 0x5f23ae668ce7926d, - 0xfef74d1da0846719, 0x54478408e68cb7d4, 0xee27ddaf88c6fe68, - 0xb7ac7031e81867ca, 0xf1168f818ec6c36d, 0x1dd0b734a83b019a, - 0xd6ae30d4142b54fe, 0xcd860c721ccb80fb, 0x068acf8493794756, - 0xd4ada0be58681307, 0x13ffe0f64ca540ed, 0xffc1d7a3401aec02, - 0xd81c4d865cf95fb9, 0x1dd0793acede62e0, 0xa6722abbca8fe4cf, - 0x5453d3e4111a7e40, 0xf29b3e3204c9dcd2, 0x23be2980e43117f7, - 0x74e2ccbc286f08eb, 0x19ef7c0f9496003a, 0xbfbf1c3e49b27987, - 0x6e6c179eb4a82c70, 0x07f4e184216bc4fc, 0xf17fbc4254927554, - 0xe57696b70a45b1b6, 0x6d3b144631b320e8, 0xccf8729792c75a2d, - 0xe832495b41fa980b, 0x5c96cfdc7b227d34, 0xc4dca234ef4e43f4, - 0x5fc801abf9abe307, 0xe41e3c5076d88f4d, 0x522346200ddec3c3, - 0x72bed1946fd7aaa4, 0x0ac1f84dcc335f96, 0x3af78db5e0a47670, - 0x6100ebf1481f1caf, 0xf5fd10037fc651a3, 0xa01227d8944665f3, - 0x7217681c4bbc9420, 0x4adee538e3eb10d1, 0x35e1761ad96de9a7, - 0x8b370aef9613bfba, 0x824506f749eeaf59, 0x85e805fa04423991, - 0xb61e9c33283c3de7, 0xc79721bbcb039ed6, 0x04e1c19a3a1e6639, - 0x6aaf6346b68dd638, 0x601a4b496be6d0c4, 0x3ece355f91c41787, - 0xd2fc8998448d7888, 0xd7529804f843efa9, 0xabdcc38a288536aa, - 0xdd323e48a9718648, 0x2090279c0030a52a, 0xe2f90faca88a3cd1, - 0x3e0c4e92fc50e4aa, 0xa26d308798e801dd, 0x432eefeedee8c02e, - 0xca4ce494614b77df, 0xbba82911e838066d, 0x4b00821016adee4b, - 0x4cf6e526dfb5a20f, 0x5b8466495142cba2, 0xe28ac1406e88a68c, - 0x8511e5f9d3100999, 0x05acbfe02798890b, 0x74c249c7ce4a8425, - 0xdbe7468d09bc34bc, 0x11079ab10e3b9b58, 0xb7788dec9032035a, - 0xb7e8daa786513f80, 0x34c3288831f46b45, 0x014cce5f0c21ecc6, - 0xc6a8f7b024551a28, 0x49784e902e207fd8, 0x4720d32af0b55158, - 0x8df3ec5de0c1da00, 0xf4db677b2c9e6853, 0xaa419abea78d312d, - 0x181e0f91bd757443, 0xa8c45136fada083b, 0x91303b93f5f0582c, - 0x883b95c6ddc62a08, 0x93186a8875fe952b, 0xd94f533928e957e2, - 0x6ba343003e10c172, 0xc8623b620c715d6a, 0x8ca0c512e180e244, - 0xdc9b74c2536b6216, 0x8eb5fdc61b295d96, 0x2ad83966b37c95ba, - 0xb90bf154ac5edec9, 0x902cf847b326cfb3, 0x7b02d0c0ca7808ca, - 0x492f310d003ea15f, 0x3eb6497a47c95990, 0x5d46b0ced31428b7, - 0x081afa67d1986157, 0x043482ec286b20eb, 0xc103c8f18c1a2a53, - 0xe8e9995a81481e83, 0x6bb3295822bc90b5, 0xeec75297a3fa5672, - 0x591c8440c4857412, 0x74947f455aaf24ad, 0xcf0e571586ec77a9, - 0x0c2553ea8c0400ad, 0x380219118066255f, 0x7595adb88b15ebe2, - 0xb33c00696c64ae23, 0xa143516ddd7c9857, 0x39179af229248d26, - 0x65d387a6f2ee2079, 0x89f8a9b21cd2f195, 0xbfef032d25df92e6, - 0x6b7e18a36c69da71, 0x4b3b15f6c28974e6, 0x032a75917f6c544c, - 0xe3b97ecca6d287cd, 0xa4a563110d3cda81, 0x35e09e8134f4e7f1, - 0xc9419dd03a9a390e, 0x7b86fae9000fd329, 0x1e044f8d54fe74c3, - 0x9c4991d7a47e9666, 0xfb485f3a1df4fdb6, 0xb11519969eeb94ff, - 0x3224ea1c44caeb8d, 0x86570bbd7cc6b80d, - }; #else constexpr uint64_t kGolden[kNumGoldenOutputs] = { 0xe5a40d39ab796423, 0x1766974bf7527d81, 0x5c3bbbe230db17a8, -- cgit v1.2.3